尔雅Introduction To Statitics章节答案(学习通2023完整答案)
73 min read尔雅Introduction To Statitics章节答案(学习通2023完整答案)
online weekly quiz (week three)
1、尔雅A survey was conducted to determine how people rated the quality of programming available on television. Respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality). The节答 stem-and-leaf display of the data is shown below. What percentage of the respondents rated overall television quality with a rating of 80 or above?
A、0
B、案学4
C、习通96
D、完整100
2、答案A survey was conducted to determine how people rated the quality of programming available on television. Respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality). The尔雅 stem-and-leaf display of the data is shown below. What percentage of the respondents rated overall television quality with a rating of 50 or below? Stem Leaves 3 2 3 4 0 3 4 7 8 9 9 9 5 0 1 1 2 3 4 5 6 1 2 5 6 6 7 0 1 8 9 2
A、11
B、节答40
C、案学44
D、习通56
3、完整A survey was conducted to determine how people rated the quality of programming available on television. Respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality). The答案 stem-and-leaf display of the data is shown below. What percentage of the respondents rated overall television quality with a rating from 50 through 75? Stem Leaves 3 2 3 4 0 3 4 7 8 9 9 9 5 0 1 1 2 3 4 5 6 1 2 5 6 6 7 0 1 8 9 2
A、11
B、尔雅40
C、节答44
D、案学56
4、Every spring semester, the School of Business coordinates a luncheon with local business leaders for graduating seniors, their families, and friends. Corporate sponsorship pays for the lunches of each of the seniors, but students have to purchase tickets to cover the cost of lunches served to guests they bring with them. The following histogram represents the attendance at the senior luncheon, where X is the number of guests each graduating senior invited to the luncheon and f is the number of graduating seniors in each category. how many graduating seniors attended the luncheon?
A、4
B、152
C、275
D、388
5、Every spring semester, the School of Business coordinates a luncheon with local business leaders for graduating seniors, their families, and friends. Corporate sponsorship pays for the lunches of each of the seniors, but students have to purchase tickets to cover the cost of lunches served to guests they bring with them. The following histogram represents the attendance at the senior luncheon, where X is the number of guests each graduating senior invited to the luncheon and f is the number of graduating seniors in each category. If all the tickets purchased were used, how many guests attended the luncheon?
A、4
B、152
C、275
D、388
6、A professor of economics at a small Texas university wanted to determine what year in school students were taking his tough economics course. Shown below is a pie chart of the results. What percentage of the class took the course prior to reaching their senior year?
A、14%
B、44%
C、54%
D、86%
7、When polygons or histograms are constructed, which axis must show the true zero or "origin"?
A、the horizontal axis
B、the vertical axis
C、both the horizontal and vertical axes
D、neither the horizontal nor the vertical axis
8、When constructing charts, the following is plotted at the class midpoints:
A、frequency histograms.
B、percentage polygons.
C、cumulative percentage polygon (ogives).
D、all of the above
9、1. True or False: Given below is the scatter plot of the price/earnings ratio versus earnings per share of 20 U.S. companies. There appear to be a positive relationship between price/earnings ratio and earnings per share.
10、True or False: Given below is the scatter plot of the market value (thousands$) and profit (thousands$) of 50 U.S. companies. Higher market values appear to be associated with higher profits.
Chapter 6 Normal distribution
assignment for May 10th
1、All the major stock market indexes posted gains in 2010. The mean one-year return for stocks in the S&P, a group of 500 very large companies, was 12.8%. The mean one-year return for the NASQAD, a group of 3200 small and medium-sized companies, was 16.9%. Historically, the one-year returns are approximately normally distributed, the standard deviation in the S&P 500 is approximately 20°%, and the standard deviation in the NASDAQ is approximately 30% (1) What is the probability that a stock in the S&P 500 gained value in 2010? (2) What is the probability that a stock in the S&P 500 gained 10% or more in 2010? (3) What is the probability that a stock in the S&P 500 lost 20% or more in 2010? (4) What is the probability that a stock in the S&P 500 lost 40% or more in 2010? (5) Repeat (a) through (d) for a stock in the NASDAQ. (6) Write a short summary on your findings. Be sure to include a discussion of the risks associated with a large standard deviation.
2、A survey in 2005 found that the monthly cell phone bill is $63 for an average user and $77 for a user who uses advanced features. Assuming that monthly cell phone bills follow a normal distribution with the respective means and a standard deviation of $7, find the probability （1）that an average user's cell phone bill is less than $70 per month. （2）that a user of advanced features is able to keep his cellphone bill less than $85 per month （3）that an average user's cell phone bill is above $77 per month （4）What percentage of advanced features users will pay more than the amount that the top 90% of average users pay?
Chapter 7 Sampling and sampling distributions
exercise
1、The amount of time a bank teller spends with each customer has a population mean of 3.1 minutes and standard deviation of 0.4 minute. If you select a random sample of 16 customers, A) What the probability that the mean time spent per customer is at least 3 minutes? B) There is an 85% chance that the sample mean is less than how many minutes? C) What assumption must you in order to solve a) and b)? D) If you select a random sample of 64 customers, there is an 85% chance that the sample mean is less than how many minutes?
